Jet measurements in pp, p--Pb and Pb--Pb collisions with ALICE at the LHC

We present a systematic study of jet measurements in pp, p--Pb and Pb--Pb collisions using the ALICE detector at the LHC. Jet production cross sections are measured in pp collisions at $\sqrt{s}$ = 2.76 and 7~TeV, in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02~TeV and in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76~TeV. Jet shape observables and fragmentation distributions are measured in pp collisions at 7~TeV. Jets are reconstructed at midrapidity in a wide range of transverse momentum using sequential recombination jet finding algorithms ($k_{\rm T}$, anti-$k_{\rm T}$, and SISCone) with several values of jet resolution parameter $R$ in the range 0.2 -- 0.6. Measurements are compared to Next-to-Leading Order (NLO) perturbative Quantum Chromodynamics (pQCD) calculations and predictions from Monte Carlo (MC) event generators such as PYTHIA, PHOJET and HERWIG. Jet production cross sections are well reproduced by NLO pQCD calculations in pp collisions at $\sqrt{s}$~=~2.76~TeV. MC models could not explain the jet cross sections in pp collisions at $\sqrt{s}$ = 7 TeV, whereas jet shapes and fragmentation distributions are rather well reproduced by these models. The jet nuclear modification factor $R_{\rm pPb}$ in p--Pb collisions is found to be consistent with unity indicating the absence of large modifications of the initial parton distribution or strong final state effects on jet production, whereas a large jet suppression is observed in Pb--Pb central events with respect to peripheral events indicating formation of a dense medium in central Pb--Pb events.Comment: 6 pages, 5 figures, 7th International Conference on Physics and Astrophysics of Quark Gluon Plasma, 1-5 February, 2015, Kolkata, Indi

Wage Inequality in the United Kingdom, 1975-99

U.K. cross-sectional wage inequality rose sharply in the 1980s, continued to rise moderately through the mid-1990s, and has remained essentially unchanged since then. As in the U.S., increases in within-group inequality account for a substantial fraction of the rise in wage dispersion during the period 1975-99. Compositional shifts in the occupational and industry structures of aggregate employment also had important effects on the evolution of wage inequality. The convergence of the wage distributions for men and women has, however, had a stabilizing effect on the overall wage distribution. Copyright 2002, International Monetary Fund

On the fields generated by the lengths of closed geodesics in locally symmetric spaces

This paper is the next installment of our analysis of length-commensurable locally symmetric spaces begun in Publ. math. IHES 109(2009), 113-184. For a Riemannian manifold $M$, we let $L(M)$ be the weak length spectrum of $M$, i.e. the set of lengths of all closed geodesics in $M$, and let $\mathcal{F}(M)$ denote the subfield of $\mathbb{R}$ generated by $L(M)$. Let now $M_i$ be an arithmetically defined locally symmetric space associated with a simple algebraic $\mathbb{R}$-group $G_i$ for $i = 1, 2$. Assuming Schanuel's conjecture from transcendental number theory, we prove (under some minor technical restrictions) the following dichotomy: either $M_1$ and $M_2$ are length-commensurable, i.e. $\mathbb{Q} \cdot L(M_1) = \mathbb{Q} \cdot L(M_2)$, or the compositum $\mathcal{F}(M_1)\mathcal{F}(M_2)$ has infinite transcendence degree over $\mathcal{F}(M_i)$ for at least one $i = 1$ or $2$ (which means that the sets $L(M_1)$ and $L(M_2)$ are very different)

Local-global principles for embedding of fields with involution into simple algebras with involution

In this paper we prove local-global principles for embedding of fields with involution into central simple algebras with involution over a global field. These should be of interest in study of classical groups over global fields. We deduce from our results that in a group of type D_n, n>4 even, two weakly commensurable Zariski-dense S-arithmetic subgroups are actually commensurable. A consequence of this result is that given an absolutely simple algebraic K-group G of type D_n, n>4 even, K a number field, any K-form G' of G having the same set of isomorphism classes of maximal K-tori as G, is necessarily K-isomorphic to G. These results lead to results about isolength and isospectral compact hyperbolic spaces of dimension 2n-1 with n even

A review of the economic burden of ADHD

Attention-deficit hyperactivity disorder (ADHD) is a common disorder that is associated with broad functional impairment among both children and adults. The purpose of this paper is to review and summarize available literature on the economic costs of ADHD, as well as potential economic benefits of treating this condition. A literature search was performed using MEDLINE to identify all published articles on the economic implications of ADHD, and authors were contacted to locate conference abstracts and articles in press that were not yet indexed. In total, 22 relevant items were located including published original studies, economic review articles, conference presentations, and reports available on the Internet. All costs were updated and presented in terms of year 2004 US dollars. A growing body of literature, primarily published in the United States, has demonstrated that ADHD places a substantial economic burden on patients, families, and third-party payers. Results of the medical cost studies consistently indicated that children with ADHD had higher annual medical costs than either matched controls (difference ranged from $503 to$1,343) or non-matched controls (difference ranged from $207 to$1,560) without ADHD. Two studies of adult samples found similar results, with significantly higher annual medical costs among adults with ADHD (ranging from $4,929 to$5,651) than among matched controls (ranging from $1,473 to$2,771). A limited number of studies have examined other economic implications of ADHD including costs to families; costs of criminality among individuals with ADHD; costs related to common psychiatric and medical comorbidities of ADHD; indirect costs associated with work loss among adults with ADHD; and costs of accidents among individuals with ADHD. Treatment cost-effectiveness studies have primarily focused on methylphenidate, which is a cost-effective treatment option with cost-effectiveness ratios ranging from $15,509 to$27,766 per quality-adjusted life year (QALY) gained. As new treatments are introduced it will be important to evaluate their cost-effectiveness to provide an indication of their potential value to clinicians, patients, families, and third-party payers

Oscillations in active region fan loops: Observations from EIS/{\it Hinode} and AIA/SDO

Active region fan loops in AR 11076 were studied, in search of oscillations, using high cadence spectroscopic observations from EIS on board Hinode combined with imaging sequences from the AIA on board SDO. Spectra from EIS were analyzed in two spectral windows, \FeXII 195.12 \AA and \FeXIII 202.04 \AA along with the images from AIA in 171 \AA and 193 \AA channels. We find short ($<$3 min) and long ($\approx$9 min) periods at two different locations. Shorter periods show oscillations in all the three line parameters and the longer ones only in intensity and Doppler shift but not in line width. Line profiles at both these locations do not show any visible blue-shifted component and can be fitted well with a single Gaussian function along with a polynomial background. Results using co-spatial and co-temporal data from AIA/SDO do not show any significant peak corresponding to shorter periods, but longer periods are clearly observed in both 171 \AA and 193 \AA channels. Space-time analysis in these fan loops using images from AIA/SDO show alternate slanted ridges of positive slope, indicative of outward propagating disturbances. The apparent propagation speeds were estimated to be 83.5 $\pm$ 1.8 \kms and 100.5 $\pm$ 4.2 \kms, respectively, in the 171 \AA and 193 \AA channels. Observed short period oscillations are suggested to be caused by the simultaneous presence of more than one MHD mode whereas the long periods are suggested as signatures of slow magneto-acoustic waves. In case of shorter periods, the amplitude of oscillation is found to be higher in EIS lines with relatively higher temperature of formation. Longer periods, when observed from AIA, show a decrease of amplitude in hotter AIA channels which might indicate damping due to thermal conduction owing to their acoustic nature.Comment: Accepted for publication in Solar Physic